Slot machines are gaming devices which incorporate a plurality of reels rotatable about a common axis and on which are carried at the periphery a plurality of indicia indicating the position each reel stops. Usually the reels are set into motion by pulling a lever and upon stopping, the angular positions of the reels are detected to determine the amount of payoff to the player.
In the original mechanical machines the reels were stopped by actuating a brake or a tripping arm/pin which moved into grooves (cutouts) in each reel's index wheel on a random timing basis. This method was carried over to the electromechanical machines of the 1960's and to date insofar that the basic stopping of the reels is by timewise releasing an index pin into grooves in index wheels attached to the reels with indicia displaying the game result. These varying depth grooves enabled, via physical contact closures of wipers being a part of the index arm mechanism and physical wiring to relay logic, payouts in accordance with the designed payout schedule which again was directly related to the probability of occurrence of the indicia--symbol--displayed on the reel itself. Such machines are directly susceptible to wear and tear (including erroneous electrical paths due to dirt and coin dust in particular, in the wiper contact area) as well as intentional tampering by both the player and unethical operators and their employees adversely affecting the regulations required for randomly probabilistic payoff.
Beyond the above-described slot machine devices there has followed now the electromechanical gaming devices employing a plurality of reels rotatable about a common axis and set into rotation by the pulling of a lever. However, in these newer devices an electronic random number generator of some type is energized which generates one number corresponding to each of the various positions at which the reels can be stopped. As the game is played, each reel is stopped in sequence with the other reels at a position corresponding to each subsequent number generated. The angular rotational positions of the reels are detected at all times and the brake is engaged when the reel position corresponds to the random number generated for that reel. The probability for paying off on a combination of indicia on presently used machines, as described above, is dependent on the number of reels, the number of different angular rotational positions at which the reels can be stopped, and the number of winning combinations of indicia. In other words, the lowest probability for payoff that can be offered on presently used machines are 1 to N.sup.R where N is the number of angular rotational positions on each reel and R is the number of reels. Thus, for a three reel machine having 20 stop or index positions on each reel, the lowest probability that can be offered is 1:20.sup.3 or 1:8000. For a machine to be commercially viable, there is a limit on the largest amount that will be paid for any such single indicia combination.
The above reasoning explains why the slot machines which offer greatly increased payoffs are usually very large machines in terms of the number of reels and stop positions. The large machine provides the physical size to allow an increase in the number of reel stop positions as well as number of reels to increase the probability against payoff on any one position.
It should be noted that the market demands higher and higher payoffs to maintain and increase player appeal, yet the casino or operator must be assured that the probability of win and payout allows for a reasonable business profit. Generally the profit-hold objectives before taxes and operational costs that are deducted are in the range as low as 2.7% and generally up to 15%. Hence, the higher payoff for a winning indicia combination must be counterbalanced with less probability for the high win combination of indicia.
It is therefore the purpose of this invention to increase the capability of the designer to include high payoffs without increased physical size of the machine and with uniform presentation of the games of different models to the player. It should be noted that the players perceive larger machines as being less "good" in terms of winning and payout chances. That is, large physical machines and a large number of reels develop an attitude in the player which affects the play and acceptance of the machine although this does not always coincide with the true mathematical reality and probability of payout of the machine. This attitude affects the play appeal of the device and its revenue-producing capability and this player's attitude is quite important in marketability of the slot machines both to casinos and operators as well as to the "player" slot location. Also, this attitude may be more influential on whether or not the machine is played than published figures showing the payoff odds. Thus, it is important to make a machine that is perceived to present greater chances of payoff than it actually has within the legal limitations that games of chance must operate.
It is a further purpose of the present invention to provide a machine on which the probability is easily designed and on which high value payoffs can be offered on a standard three or four reel machine with correct probability that makes the high value payoffs feasible. The major benefits of such a machine besides the marketability and competitiveness to other slot machines and pure electronic or video games and gaming devices are:
(1) Prevention of tampering of the game to create illegal wins and payoffs.
Note that this feature of the invention protects both the operator and more importantly, the public or player as well as the licensing agency.
(2) Standardization in design and production by cost effectiveness of the product line across all conceivable product models and payoff probabilities and odds, i.e. payback of a win for a given coin insert.